Circuits-flat type switch



Jan. 17, 1956 J, WICKS CIRCUITS-FLAT TYPE SWITCH 8 Sheets-Sheet l Filed March 9, 1953 INVENTOR. JOHN Wl CKS Wfl/Wm ATTY.

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CIRCUITS-FLAT TYPE SWITCH 8 Sheets-Sheet 2 Jan. 17, 1956 Filed March 9, 195s INVENTOR JOHN WICKS BY 7% ATTY.

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8 Sheets-Sheet 3 Jan. 17,'1956 CIRCUITS-FLAT TYPE SWITCH Filed March 9, 1953 INVENToR. JOHN wxcxs BY I 7% /l/'f Jan. 17, 1956 J. WlcKS CIRCUITS-FLAT TYPE SWITCH 8 Sheets-Sheet 4 Filed March 9, 1953 oon Il-III Il.. Q

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Jan. 17, 1956 J. WICKS CIRCUITS-FLAT TYPE SWITCH Filed March 9, 1955 8 Sheets-Sheet 6 INVENTOR.

JOHN WIGKS Jan. 17, 1956 .1. wlcKs CIRCUITS-FLAT TYPE SWITCH 8 Sheets-Sheet '7 Filed March 9, 1955 INVENTOR. JOHN WIGKS Wj l Jan. 17, 1956 J. wlcKs CIRCUITSFLAT TYPE SWITCH 8 Sheets-Sheet 8 Filed March 9, 1953 mowul.

Swing 2 2 *IEM mwllllll INVENTOR. JOHN WIGKS BY mw rwl . theswtch upon its second opt-zration;V

t This tinventionfrelates; `in tgenerahtofetelephonc zqsystems,L and moret particularly; to `an,A automatic=.system vutilizing multi-directionalstepfbygstep switches:` -l

It is man. object of `this invention?` to.; develop .-newzfand novel` system` utilizing `a 4dattype switch capable of tmovf. ingy a` plurality of wipersrinat selectivcmnumber of rotary:y and radial steps.,`

A feature of this inventionis theteconomyandsimplicity achieved` i in they` system describedA t hereim; which.` system: utilizes a switch `which `.makesA use of f onlyl, two magnets;A one stepping the wipersLthereinwinntwo directions `under p 2,731,515 Patented Jan. 1.7.1956

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`. tiontinqresponseto..impulses-:received while theV control magnet isenergized` for a firsttime; the stepping magnet` will;` move :the'gwipers .in a radialdirection in `response to impulses received;while` the control magnet isdeener.. gized;` andwwhen :the .control magnet energizes a second time the wiperswill benreleased first in axradialdirection, then inthe rotarydirection. Said Sengebusch switch has `avv-iper` carriage, normally locked against rotation,

and a driving segment. When the switch is initially seized in :.Wicks..` system, the `control magnet is energized, its operated.armaturecausing the carriage to be unlockedlto permit rotational. movement andto be` locked with the drivingfsegment.:` A first series of impulses received by ther switchxoperatewthe driving magnet, which magnet moves .therdriving segment (andthe carriage locked therel with) in a rotary direction. At the end of said series of the control of .the other. The control magnet will release Another feature of this invention.. is; ther-economy achieved` by `useof a newA and novel. allfrelayontrol unit; associated with each' first `selector `but,tpreferablywrnountcdl separately, whichnunit `willlcontrol all selectors andqtlie. connector in; a switch. train set: `,11D `1 over the `first. selector associated therewith.` p M `1 t Another .feature` is fthe provision@ lof arnewxand `1`novel means whereby both `local.",andfncorning ttoll. callsizwillr be routed` t over t the samengroup 1 tof .connectors and `interme-e` diateselectorsu;` M l. .f t

Another feature of `thisyinventionsis th'eusexoanewi and" novel v connector, wherein tone :set of.l wipers-extends a call. `to any .l predetermined :line inteither, zof.` two; u groups of lines accessible `thereto in responseptottwoadigits; i

Another feature is ,the` new-andnovel mannerroftcoms plating` inter-exchange `calls rover.; 2 wire i trunks. :without using repeaters. t i Further features` of f this invention. will` be evident tupon aperusal of the-following,disclosureinwhicht Fig.` l `shows ablockgdiagram ofsalztypical substatiom customer; line, line circuit, `finden.` and 1 linder-allotter- :and aschematic diagramof al switch train cnntroltunit;LA Figr2shows a 100-line'firstselectorswitch..` t

` Fig.V 3 `shows a t100-line `xinte'rmediate selector t switclm Figs 4 shows `a .100-line .connector .Switchs `l Fig. "5 shows the connector.` bank)` .wiring fortan iindividual linemand aP. B.\,X. 1 .l f y. Eig. 6 shows an inter-,exchange selectors` y i ands7A show the selectortbank wirlizrglforfinter-` exchange calls. i 1 w i l V1 Eig.` 8 shows a tolltrunk control unitaV Figli) shows aZOO- lineselector:r i u .t Fig.` `10 shows A,a IZQO-linetconnector `withlstwo fsetssof wipers.,` t

Fig. 1l shows a.20l)linefr-corinectorrwitlr.one set-sof wipers,.and"v y n n :vul-"j l Fig. 12shows aparty-lin'e connector. Y

Thesecircuts,have` been` developed `foruscwith-tile` impulses,` the control` magnet restores, its armature restoring to cause the carriage to` be free of `the driving segment and to be locked against rotational movement. Gears, mounted on'the wiper carriage and cooperating withlthe `wipers and thedriving segment, cause thewipers to be 'moved radially when 'the driving magnet is' again operateditto `rotate `the driving segment. Associated with thedrliving `segment -is aldetent for preventing restoration ofthe' segmentto notmal. Associated with the armature of thefcontrol magnet is a release pawl which can engage said detent only when the driving segment is olif-normal." Thereforegfwhen said controlmagnet is operated a second time and said drivingtsegment is off-normal, said pawl will engage ttlbdetent and remove it from `contact with the driving segment; and the carriage, wipers and driving l segment will all restore tonormal.

ilat type rswitch showninthe veo-pending patentiapplicaf tion of HanswSengebusch; ImprovementsinFlatType Switches, Serial `No.` 2361377,"iileclluly12;jl95l,` now PatentNo. 2,648,54085` Y,

The mechanism :of the switch is..,designedso thatgzthe steppingmagnet movethewipers" i'la' rotary direc-y Thelmeans forI energizing the control magnet of a` switch@ for atsecond time, to control this release,` differs in the variousfswitches-i e. control `magnet M200 ofthe first :selector in Fig. 2`isreoperated over release lead 233; Mw'ofthe Lintermediateselector in Fig. 3, over a circuit irlcludingucontacts A301 release control relay R300; and TM400 of the `connector in 4, over a circuit includinglcontactsyll of ring cut-off relay Rfllt).` This is donekinorder to avoid the use of a fourth wiper in the selector andconncc'tor switches. The first operationof eachacontrol magnetwis controlled over that conductor in thenswitch tofwhich" the negative side of a 'subscriber line isvextended.; t t

Theoperation'of each stepping magnet is `controlled overthat conductor in theswitch to which the positive side ofa` subscriber line is extended.

Onalocal calls thelring cut-oli' relay-. e. R440 of Fig. 41-is .operated'upon seizure of the switch, restored upon operationwfofctheswitching relayi. e. R412() of Fig. 4- andthenreoperatedwhen the call is answered at the called substationxe However, on toll calls, the ring cut-off relay is held.:operated Sover Vthe` extra control `conductori. e; 453-thereby' to `permit toll connections, with ringing controlledzbythe operator, such `callsbeing set up over the same group of selectors and `connectors'as local connections.` p

w The fselectorishownin Figf 9 and the connector shown inw Fig;l 10.I thavebank terminals `for 20G-lines arranged in` ZOnlevels of. l0 lines;for `each level.` `As one set of Wipers moves `over-one set of contacts, .the` other set moves over aocorrcsponding, set` of` contacts. In the selector. this rcsultstina.more-,rapid search for anidle trunk.` In the connector; the desired` trunk is :determined `bylthe'set Soi incoming conductors ,over` which al call `is received.

i The connector Lshown in-Fig4 l1 has itsbankterminais `arranged in 10 levels `with 20 `lines to a level. This conneit-ofrdepifndslupoll: thwipcrstmaking fromfl .fottilo Inter-exchange calls may be completed either by the use ofthe controlunit of.Fig. 1 or under conditionsin which the relays of said unit are completely removed from the control circuit. The former is preferable under normal .conditions as the control relays-willltake the place of a repeater on an inter-exchangetr'unk. .Thelatter is required when it is desired to provide a control circuit may be any one of several types well known .in theart.

It is assumed that one side is grounded so thatl a path avenue y relay R100 will restore and reope'rate in response to each 4,impulse received..ln response to the first impulse, R100 restoring and Vclosingvcontacts 102, completes an obvious circuit for operating R140 and a circuit for en-k ergizing steppingmagnet M210, the latter circuit extending from ground, over contacts 127, 102, 111, 134, 122 and 186, conductors 159 and 231,1.con'tacts 221, through the winding of M210 to battery. R140 operates and at contacts 141 completesan obvious circuit for operating R150.` `R150 operating prepares L at contacts 154 a circuit yforlater operating relay R160 in "series with R150. M210 energizes to drive the wipers one rotary step. Oli-normal 4 contacts 247'are closed to prepare to second operating for Vtone may be completed to a grounded conductor inl any one of the controlunits.

,The ringing generator is not shown and may be any one ofseveral types vwell known in the art.

Local calls n v.

YReferring more particularlyl tofldi'gs. 1, v2,73. and 4, establishment ofalocal,connectiony will be described. As-l sume a four-digit director number systemv requiring the use of two selectors and a connector as shown in said figures. Conductors 159, 169, 179, 189 and 199 of Fig. 1

Vwill be tied to conductors 231, 232, 233, 234 and 235.

of Fig. 2 respectively. Contacts. 236,237, 238 and 239 of Fig. 2 will terminate conductors 343, 344, 345 and 346 of'Fig. 3 respectively. Contacts 365, 366, 3,67 and 368 of Fig. 3 will terminate conductors 451, 452, 453gand 454 of Fig. 4. p ,A Y

Assume a subscriber initiates a callV from `substation 195 and that the lines 193 and 194 are extended to conductors 117 and 118 in a manner well known inthe art. A circuit for operating line relay R100 is completed from ground, through the lower winding ofk R100, over contacts 109 and 124, conductor 118, extended-line 194, substation 195, extended line 193, conductor117, contacts 121 and 106, through the upper winding of R100 tobattery.

R100 operates and at contacts 101 completes an obvious circuit for operating hold relay R110. R110 operates and at contacts 111` prepares a circuit for changeover relay R140 land for steppingmagnet M210-of the selector;

' at contacts 112 marks the control unit-selector link busy over private conductor 119 and partially preparesfa circuit for switching relay R130; at contacts 113 completes a circuit for operating series relay R145 and control` magnet M200 from ground over contacts 113, the lower winding of R145, contacts 163, 175, 132 and 125, conductors 169 and 232, contacts 223 and 216, through the winding of M200V to battery; at contacts 114 again opens the .already open release circuit for the selector of Fig. 2. R145 operates, at contacts 147 preparesa circuit for relay R150 and at contacts 149 partially prepares a circuitlfor changeover relay R160. M200 operates to prepareV the switch for rotary stepping and at contacts 202prepares a holding circuit for itself.

When the operation of R110 closed contacts 115, anY

alternating current was imposed upon R145 by dial tone circuitfor M200, oi'normal-contacts 246 opento` remove dial vtone from the line, ott-normal contacts 217 close to prepare an operating circuit for 'interrupter relay R185 and to provide an alternate holding circuit for M200, and ott-normal contacts 248 close to complete a circuit for operating relay R160fin series with operated relay R150. However R160 does not operate'a't thisv time since it is short-circuited by ground at contacts 141. YAt the end of the firstl pulse, R100 reoperates and M210 restores. In

response tofreach additional impulse, lthe wipers will be moved onelrotary step. At the end of the rst'digit, R140 restores, and at contacts 141 removes the'ground which was short-circuiting R160. R160 now 'operates in series withV R150 over a circuit extending from ground, over contacts 249, 248 and 225, conductors 234 and 189, con` tacts 154, the winding of R160, contacts 149 .and the winding-of`R150 to battery. Atcontacts 161,R160 locks itself independent of springs 149; at contacts 162, `fur ther.V prepares a circuit for operating R185; and at contacts 163, opens theroperating circuit of R145 and M200,

bothof' which restore to normal. M200 restores to complete at contacts 201 a circuit for-operating R185, said circuit extending from ground, over contacts 229, 211,

201, 217 and 223, conductors 233 and 169, contacts 125,`

v 132, 175 and 162, through the Winding of R185 to batequipment (not shown) over contacts246 and the pre# viously described circuit through relay 245 and Econtrol magnet M200.k Transformer action in R145 results in the upper winding of R145 picking upthe dial tone current fluctuations, and transmitting them to substation195 Yover a circuit extending from line 194, conductor 118, contacts 124.and 109, capacitor 103, the upper winding of R145,

capacitors 104 and 116, contacts 106 and 121, conductor 117, and line 193 to substation 195. n

Assume that the subscriber now dials the number of a substation on another line and thereby transmits impulses over hisline to relay R100. When the rst digit is tery. Restoration ofI M200also changes the switch mechanism. so that the wipers vwill thereafter be stepped in a radial direction. R185 operates and at contacts 187 completes a circuit for operating M210, said circuit extending from-ground, over contacts'187, conductors 159 and231, contacts 221, throughl the winding of M210 to battery. M210 operates, moves the wipers one stepradially,`and at contacts 211 opensY the operating circuit of R185. R185 restores and at contacts 187 opens the operatingy circuit to M210. M210 restores. Y

If the contacts, uponwhich wipers 241,242, 243, and 244 are standing after this first step, terminate in anidle intermediate selectori. e. the selector shown in Fig. 3, a circuit for operating switching relay R220 will be cornpleted from battery, over resistor348,'contacts 337, conductor 346, contact 239, wiper 244, the upper winding of R220, conductors .235 and 199,l the lower windingof R120, and contacts to ground. It will be notedvthat R does not operatein this circuit and will operate only on inter-exchange callsrequiring use of' repeaters, as will be explained later. R220 operates; at contacts 223, which operaterapidly, opens `the operating circuit of R185 to prevent a reoperation thereof when M210 restoresyat contacts 221, opens the circuit to M210; at contacts 225, opens the operating circuit Vof-R and R150; at conltacts 227and 228 (contact 228 closing first to insure locking of R220), completes a locking circuit for R220 and places ground .through'Rl20on wiper 244;--and atfcontacts 222, 224, 226, and 227 extends the control circuits to contacts 236, 237, 238 and 239 by way of wipers 241,

242, ,243 and 244. R150 and R160 of Fig. 1 restore, R160 contacts 224, wiper 242, contact 237, ,conductor 344, contacts,l 333 throughk vthe winding lof M310t o tetris battery. R145 and-M310 operate; release@control.frelayr R300 operates over a` circuitextendinggfrorn grounded. contact 239 (previously described) over conductor 346,"

contacts` 341, through,thewindingt` ofR300 to battery R300 will remain energized luntil ,ground `is 4rern'ovediat contacts 115 by the hold relay R110.

If the intermediate selector `of Fig.; 3, Vhad been busy;

series relayR145,. switching relays R2201andR330', release controlfrelay R300 control magnet M400Vandfring cut-v.,` oij` relay R440l are vnow the only relays .in `an `operated position.

UIL

ground would havebeen placed onits private contact 2397, overa circuit` similar` to that extending fromsground over` contacts 115, the lower lwinding oflrelay` R1`20,.condut`c` tors 199 and 235,` contacts 227, andwiper 244m` contect 239: R220, could not operate to openthe circuitffor operating R185; R135` would reoperateiwhenl M2101 re-` stored; M210 would reoperate whenR'1851reope1'ated` thereby to step the wipers 241, 242 243, and` 2441t0 the contacts terminatingin theneltt accessible interljnediate.r

selector. If the latter` selector were busy, the `wipers would beistepped to thenext contacts in )a similaremanner and so on until an idle trunkiwas foundtor allftrunkswere found busy. If alltrunks were` busy, the wipers `wouldd'ie. stepped to` the eleventh positiom.,` whereupon eleventh .0th`

normal contacts `229 would opento prevent another opter-` ation of R185, contacts 24g-would lopernto `releasetR160t and R150. When R160 restores, it completes atyconiA tacts 163 a circuit, whereby busytone from the busy tone generator (not shown) maybe sentito `the callingsubsta. tion, said.circuit extendingfrom` groundver` contacts .113, the `lower `winding `of R145, contacts.163, 175, 132 and 125, conductors 169 and` 232, contacts 223, 2,17, 201, 211fand 219, and conductor 218 to thefbusyton'e equipa ment. Transformer action `in `R145 againfresults inA the signal being induced into the upper winding of-` `R145 and being transmitted to the callingysubstation` inpa mannerr previously described. Assuming` the intermediate selector; of .Figt` `3:.wasjseized bythe iirst selector `as previously described` and was found idle, the second ydigitwill ;now.bereceivedxove1i extended lines 194 and 195;: It will be noted that, atthis time, the only relays in` an operated position areuthe `line relay R100, fthe hold relay R110` and series @relay `R145fin be noted that, when switching relay R330 operates, it

removes thebattery at contacts337afrom conductor 346; at contacts 338, extends `ground tolcontacti368 by way` of wiper 364; and, at contacts` 335, opens thecircuit :of R150 `and R160. Relay R160rrest`ores .to close :contacts 163, R145 and control "magnetlM400ioperate `in series over a circuit extendingfromlground, overrcontacts 113,

the lower winding of R145, contacts i163, 175, 1332 and 125, conductor 169 and 233, contactst224,l.wiper242, contact 237, conductor 344,` contacts 334;wiper362, contact 366, conductor 452,` contacts 425 andw457,f.through the `winding of M400 to batter-y. R145 operates tto prepare circuits for operatingR150randaR160 as, previously described; M400 operating",completesnat.contacts 401ean obvious circuit for operatingring., cut-olf` relay R440; i ,at contacts 402, completes a,.lockingcircuitrforzitself, by`a `passing otf-norrnal contactsV 457, thereby `to hold..` itself operated during the entire third digit; and at contacts 404 `prepares a `circuit for operating R160 in `series with R150.

" {,R440operates; at contacts `445 locksitselfoperated over a circuit extending trom. battery..` through `the upper winding or R440, contacts `44s and 431, conductores@ to grounded gcontact 368 `(previously,described); and .at contacts 446 again opens `the alreadyopen switchrelease circuit to control magnet M400.: Relay R160 restores.. It t.

will be noted that line and hold relays R100 and R110,

. The connector of Fig.`4 is nowready for the third digit.`

In response to the irstimpulse of the third-digit, R140,

and R150will `operate as previouslydescribed. In responseto `the `third digit, stepping.` magnet M410` will be operated .over a `circuit .extending from A ground over contacts` 127, 134 and 122, conductors 159 and. 231, contacts 222, wiper `241, contact 236, conductor 343 contacts 332, `wiper 361, contact 365 conductor` 451,. and contacts 421 yto M410, thereby to move thecom f n ector wipers 461,462, 463 and 464ina rotary` direc-` tion `to a position before a predetermined group lof con-` tacts. When the` connector wipers takeY the irst step,

oit-normal contacts .409.will close to complete the pre?.

pareducircuit` for operatingRlSO `in, series withv 11160 but R160 willnot` operateatthis time since `itswinding is-,short-circuited by ground at contacts` 141; iirstotff-` normal contacts 457 t will open the Voperating circuit` of` M400, but .M400 `will remain operated oyerithetlocking circuit previously described; and oft-normal-contacts 458 t; willclose topreparethe switchrelease circuit to M400.

Atfthje. end`. of tnemthirdj digit, changeoverrelay R140 will release and` at contacts. 141, remove the fsh`ort-v circuit from the winding 0011160. R160 will operate in series with R150- over` a circuit extending `from ground at contacts., 409 and 404,: conductor` 453, contact 367, wiper363, contacts 336, conductor 345, contact 238, wiper 243, contacts `226, conductors 234. and 1891, contacts 15.4 the winding of`R160,.contacts 149 andthe winding of R150 to battery. At contactsr163, R160` opens` the circuit of R145 and.M400 and both restore.` R145 restores-.to prepareat contacts146 `a circuit for `operating relay..R170.` M400 restores to open at contacts. 404 the ;operatingtcircuit ofR150. and R160 (both .relays restoring) and .to open at` contacts 401. the originalop-L eratingcircuit to R440; R160 `restoresjto` prepare at fc0ntaetst 164` 1an-operating` l circuit ;toy `the high,... resistance .relay.R1`9`0; R150..restores..to Vfurther.prepareat contacts 151 the circuit for operatingD R170; but R440` is held. operated `over thetpreviously described `.locking circuit.

`The connector is .now in a. position to.freceive.,the fourth digit. It will'` be noted'tl'iat,` at `'this time, line and `hold `relays R100. and R110, switching relays `R220 and R330, release control.relay R300, andring `cut-,off

relay R440Y are the onlyrelays in theoperated` position.

, 1n responseto thetirst impulse of .the.fourthrdigia` R100 releases and R140 operates `.aspreviously described.l But R140 `operating `now completes atcontacts 141 `an obviouscircuit foroperating relay R170.` R170 operates;

at ,contacts,171,. opens the already open bus-y tone circuit; at.contacts; 172, prepares a-loclring circuit for` it.- self;` at contacts 173,` prepares` an operating lcircuit for line` busy relay R180; and` atA contacts 176, prepares `a circuicfor operating interrupter relayR185. t.

It will be noted that controlV magnet M400,` when it released, prepared `theswitch for radial movement of the :wipers nectorwipers yare stepped `by magnet M140 to. thecon.- tactsterminating apredeterminedlinein that group of lines,.Ypredeterinined` by i the-third digit. Assume the last-named contacts to be 465,466, 467 and 468.` theend` of `the fourth digit R will reoperate and R140 willy restore.. Y i

If thelpredetermined` line is idle, R170will release inlresponse `to the restoration `of R; at. contacts 177, R `will `prepare `a circuit for operating relay R190; and `at contacts `175,: completesa` circuit for operating switching relay R420, said circuit extending from ground, over;.contacts `1113, the `lowerwinding of R145, contacts 163,` 175, 13,2` and` 125 `conductors A169 and' 232, contact2t24,'."wiper `242,- contacts 237, Aconductor344, conf Inwresponse tothe ,fourth digit, the con.- i

manne -7 tacts 425 and 403, the lower winding of R420 and wiper 464 to batterytnot shown) on contact 468 ofithe private conductor associated with the predetermined line. R420 will operate but R145 will not operate in series with R420. At contacts 422 and 426, R420 extends the subscriber line circuitgat contacts 424, places ground on one side of the predetermined line (R440 releases to close contacts 443); at contacts 425, opensV its own operating circuit but contacts 432 close before contacts f 425, and'R420 is held operated over alocking circuit extending from grounded contact 368, conductor 454, contacts 432, through the upper winding of R420 to battery; at contacts 427, opens the already open switch Y release circuit to M400; at contacts 431, opens the locking circuit of R440 and transfers said locking circuit to conductor 453 by means of contacts 429; at contacts 433, putsground on contact 468 by way of wiper 464, thereby 'to busy mark the predetermined line; and at con tacts 423 completes a ringing circuit to the substation on the predetermined line, said circuit extending from the ringing generator (not shown), over conductor 459, through the lower winding of R440, over contacts 423 and 441, wiper 461, kcontact 465, over that side of the Y line terminating in Acontact 461, through the ringing circuit of the substation `associated with said predetermined line, over that side of the kline terminating in contact 466, overlwiper 462, contacts 443 and 424 to ground, thereby to ring said substation. When the holding circuit of R440 was transferred, relay R190 was operated in series with R440 over a circuit extending from battery,l through the upper winding of R440, contacts 445 and 429, conductor 453, contact 367, wiper 363, contacts 33 6, conductor 345, contact 238, wiper 243, contacts 226, conductors 234 and 189, contacts 164 and 177, through the winding of R190 to ground.y R190 operates, but itsresistance is high and R440 restores. R440 restoring opens the circuit forV operating R190 at contacts 445 andlR190 will restore. When R190 operated, it completed at contacts 191 an obvious circuit for operating relay R155 from ground at contacts 139. R155 operates to complete a circuitvfor operating switching relay R130 in Vseries with itself, however ground over contacts 139 and 191 short-circuits R130. WhenR190 operates it also completes at contacts 192, a circuit for operating R150, said circuit extending from Yground,'over contacts 192'and 148;y through the winding of R150 to battery-"R150 Voperates and at contacts 139 removes ground from the `operating circuit of R155, thereby re-v moving the short-,circuit from R130, R130 operating over a circuit extending `from ground, over contacts 112, the

winding of `R130, contacts157, through the winding of R155 to battery. R150 restores in response to the restoration of R190. lR130 operating, extends at contacts 131 andA 133 a talking circuit from the calling sub* Y station to contacts 442 and 444 of the connector; at contacts 132fand 134, removes the control circuits from both Vsides of the line; and at contacts 135, vprepares a holding circuit for ring cut-off relay R440, as well as short-circuiting R190 to prevent its reoperation. It will be notedv that R440 completely restores before R130 operates.V When the called subscriber lifts his receiver,

the ringing circuit of his substation will be. short-cir'n cuited in a manner well known` in the art; the flow lof direct current in [the ringing ,circuitV will operate R440. R440 willlock itself operated Overa circuitA extending from battery,over the upper `winding of R440, contacts 445 and 429, conductor 453, contact 367, wiper 363 contacts 336, conductor 345, contact 238, wiper 243, contacts V220, conductors 234 and 189, to ground at contacts 135; 'at contacts v442 and 444, completes the talking circuit from' the calling-substation to the called substation and also completes a circuit for operating back-bridge relay .R105 which will supply battery' for ith'efcalled line and reverse the connections of relay R100 to the calling line, the former circuit extending from Athe R100 is opened and R100 restores.

callingsubstation'195, over line 193V extended to conductor 117, contacts 121 and 108, capacitor 103,Y con` tacts 133 and 125, conductors 169 and 232, contacts 224, wiperl 242,'co`ntact 237, conductor 344, contacts 334, wiper 362, contact 366, conductor 452,v contacts 426 and-444, wiper 462', contact 466, the line terminating in contact 466,'the calledfsubsta'tion, the line terminating in contact' '465, contact 465, wiper V461, contacts -442 and 422, conductor 451, contact 365, wiper 361, contacts 332, conductor 343, contact 236, wiper 241, contacts 222, conductors 231 and 159, contacts 186, 122 and 131, capacitor 116, contacts 107 and 124,

conductor 118 and extended line 194 to substation 195,'

the latter'circuit extending'from' the grounded lower winding of R105, to contacts 133, over the previously described circuit from contacts 133 to the calledsubstation and'back tocontacts 131, thence through the upper winding of R to battery; relay R440, at contacts 441V and 443, also opens the ringing circuit; and at contacts 446, again"l opens the already open switch release circuit to magnet M400. It will be .noted that at contacts'107 and 108, R105 reverses the battery connections' tothe calling line, such reversal being utilized in cases-where metering is -desired as is well known in the artiV If the called line-terminating in contacts 465 and 466'-had:b'een busy when seized by the connector of Fig. 4, ground rather than battery would have been connected to privatecontact 468 associated with the called line. As aV resultthereof, busy relay R180 would op'-v erate before R170-released over a circuit extending from f ext'ended'line 194, conductor-118, contacts V124 and 109,

through the lower winding of R100 to ground. At contacts '182,v R180 prepares a locking circuit for itself,V

saidcircuitbeing completedat contacts 174 when R170 releases Vafter a short time delay, said circuit extending from the grounded conductor 199 (previously described), over contacts 182 and'174, through the winding of R180 to battery,

.With respect to release of the switch train after completion of a; call, it will be noted that, whenthe called party hangs up, the vonly effect is to restore back-bridge relay R105. When the calling party hangs up, the line circuit 196 and nder 197 will be` restored in a manner well known in the art. Also the circuit to line relay R100 restoring, energizes R140 and opens the circuit to R110. R140 operates; at contacts 141, completes a previously described circuit for yoperating R170; and at contacts 143, again opens the Valready openrelease circuit to M200. After the operation of R140, hold relay R releases, at contacts`111, rit opens theV operating circuit of R; vat contacts 112, opens the operatingcircuit of R130'and R both'frelays'restoring; atV contacts 114, prepares a releasecircuit for M200; andat contacts 115, removes ground 'from conductor l199restoring switchingV relays R220, R330 and R420, andrcstoring release relay R300.

R300 restoring completes at contacts`301 an obvious circuit for operating M310 a second time, thereby to cause M310 to release the switch of Fig. 3. At release oE-normal `contacts 342, which are closed from the Vmorrlent M310"operates a second time until the wipers return tonorrnal, "ground isplaced yupon conductor 3746 to prevent seizure of said switch until it has returned to normal. When the `wipers return to normal, offnormal contacts 347 open the operating circuit of M310 and the magnet restores. It will be noted that therestoration of R130 will open the operating circuit of backbridge relay R105 if the called subscriber did not hang up. The intermediate selector is now restored to normal.

R420 restoring, transfers at contacts 429 the holding circuit of R440 back to the private conductor 454 and R440 will restore. R440 restores and at contacts 446 completes an obvious circuitfor operating M400 for a second time, thereby to cause M400 to release the switch of Fig. 4. Ground over contacts 401 and 455 to conductor 454 will prevent seizure of the switch until the wipers are restored to normal at which Atime release off-normal contacts 455 open. The operating circuit of M400 is opened at olf-normal contacts 458 when the wipers are restored to normal. R440 may energize upon restoration of release off-normal contacts when the wipers return to normal before M400 releases, but this will be of no consequence and R440 will restore upon restoration of M400. It will be noted that the intermediate selector restored to normal prior to the restoration of the connector and therefore is now restored to normal.

When slow-release relay R140 restores after the release of both the intermediate selector and the connector, it completes a circuit for operating M200 for a second time said circuit extending from ground over contacts 114, 128 and 143, conductors 179 and 233, contacts 247, through the winding of M200 to battery. Operation of M200 causes release of the first selector. M200 restores when off-normal contacts 24'/ open upon return of the wipers to normal. R180 may operate upon restoration of R130; and R185, upon the restoration of R140; but this will beof no consequence at this time and .both relays wiil release upon restoration of wipers 241, 242, 243 and 244 to normal; R170 Will restore the control unit and the tirst selector will be restored to normal.

` Fig. shows typical connector bank contact connections for individual lines and P. B. `X trunks. For an individual line, the bank contact 501 connected to the extra control conductor, and contact 505 connected to the private conductor are not connected to each other. The eXtra-control and private terminals of P. B. X groups are strapped as indicated `in Fig. 5-e. g. 502to 506- except for the last line-L e. 504 is not strapped to 508. When the connector switch wipers seize the vrst accessible line of a P. B. X group and said line is busy, ground on the private conductor associated with said line will be placed on the eXtra-control contact over the strapped connection. Assume contact 467 is the extra-control contact and contact 468 the private contact of said first line. As described with respect to busy lines, ground at con tact 468 will operate busy relay R180.` R180 operates; and, at contacts 183, prepares a circuit for operating in- Vte'rrupter' relay R185; R140 releasing shortly after said 'seizure completes` at contact 142 said circuit for operating R135, the circuit extending from ground at contact 467, o ver wiper 463, contacts 411 and 428, conductor 453, contact 367, Wiper 363, contacts 336, conductor 345, contact 238, wiper 243, contacts 226, conductors 234 and 18,9, contacts 164, 176, 142 and 183, through the winding of R185 to ground, R185 operates; closes contacts 187 to energize stepping magnet M410 over acircuit extending from ground, over contacts 187, conductors 159V and 231, contacts 222, wiper 241, contact 236, conductor 343, contacts 332, wiper 361, contact 365, conductor 451, contacts 421, through the winding of M410 to battery. M410 energizes, steps the connector wipers to the next set of contacts accessible thereto; and at contacts 411, opens the circuit to R185. R185 restores and M410 restores. If'other lines are busy, the same sequence of operations'are repeated. If the last `line is busy,4 the extracontrol Vcontact will not be grounded, and as with the individual busy line, R170;- `restores and puts the busy signal on the calling line'. It will be noted that R185 completes at contacts 188 an obvious circuit for holding slow-release relay R170 operated during the hunting operation. It the first accessible P. B. X line is idle, battery will be placed on the private bank contact associated therewith, the switching relay R420 will operate; and the call will be routed in the manner previously de scribed.

Inter-exchange calls Inter-exchange connections may be set up under the control of the relays in the control unit of Fig. l, or under conditions in which said relays are completely removed from the circuit. The former condition is preferable since said relays will replace a repeater. The latter condition is required however when it is desired to clear the line of talking bridges or capacitors.

For use under conditions wherein said control unit circuits will replace a repeater, applicant has devised an inter-exchange` control unit, shown in Fig. 6, with a pulsing relay- R600. Assume a call is initiated at substation 195, and is routed to the local control unit in Fig. 1,; assume said local control unit is connected` to a first selector similar to that of Fig. 2 as in the local call; assume that the bank contacts of said selector corresponding to contacts 236 and 237 terminate in trunk lines 691 and 692 respectively, which lines are connected to the inter-exchange control unit; that the bank contacts corresponding `to contacts 238 and 239 are connected` to battery through` resistors 7,10 and 711 respectively of Fig. 7; assume further that the selector of Fig. 2 is connected to the inter-exchange control unit of Fig. 6, therefore `connecting conductor 694 to 231, 695 to 232, 696 to 233, 6,97 to 234 and 698 to 235; and, asin the local call, that bank contacts 23,6, 237, 238 and 239 terminate in the selector of Fig. `3; and that the bank contacts 36S, 366, 367 and 368 terminate in the connector of Fig. 4.

In `response `to the first digit, assume that the wipers of the selector connected to the rlocal control unit will 'be stepped in a rotary direction to a position before a group of bank contacts including those contacts terminating` trunk lines 691 and 692, and then radially to `said last-mentioned contacts, which trunk lines we shall assume are idle, all in a manner similar to that. described with `respect to local calls. The switching relay of said last- `mentioned selector will operate upon said seizure over a circuit similar to one previously described and including battery through resistor 711. As in the local call, relay R160 will restore; but now relay R190 will operate over a circuit extending from battery, over resistor 710, a contact, `a wiper and a conductor corresponding to 238, 243, and 234 respectively, conductor 189, contacts 164 and 177, through the winding of R190 to ground. R190 operates; at contacts 192, completes an obvious circuit for holding R150 operated; and, at contacts 191, prepares` a circuit for operating `relay R155. Upon restoration of R160, R and line relay R600 will operate in series over a circuit extending from ground, over contacts 113, the` lower winding `of R145, contacts 163, 175, 132 and 125, conductor 169, a conductor, contacts, wiper and contact corresponding to 233, 224, 242 and 237 respectively, trunk 692, the winding of R600, contacts 627, trunk 691, a contact, Wiper, contacts and conductor corresponding to 236,v 241, 222 and 231 respectively, conductor 159, contacts 186, 122 and 134, through the winding of `R140 to battery. R does not operate in series with R600 and R140 due to `its low resistance.

4R140 operates and at contacts 141 completes a circuit `for operating R155, said circuit extending from ground, over contacts 141, 146, `152 and 191, through the winding of R to battery. The winding of switching relay R130 is short-circuited by said ground on contacts 141 to prevent its operation at this time. R600 operates and `at contacts 601 completes an obvious circuit for operating hold relay R615. R615 operates; at contacts 616, prelis controlled by line relay R600, which relay is in turn controlled by line relay R100 as follows: when R100 deenergizes in response to each impulse, it short-circuits the winding of R600 by Vclosing contacts 102 to apply ground to both sides of R600 and extends the ground from contacts 127 to the winding of R140. As a result, R600 will deenergize and at contacts 602 complete a pulsing circuit similar to that described with respect to local calls to operate the selector and connector to seize `a called line. When R100 reenergizes at the end-of each impulse, the short-circuit will be removed from R600 so that it will reenergize.

When a connection to an idle line is completed and switching relay R625 is operated in a manner similar to the operation ofy switching relay R130 as described with respect to localcalls, R625 will, at contacts 627, open `the series circuit of R600V and R140; and, at contacts 628,

place R605 in series with R140. R600 restores, and R605 operates, but R140 will restore when placed in series with the high resistance winding ofR605. R140 restores, to

remove, at contacts 141, ground from the operating circuit of R155, and R130 will operate in series with R155 over the circuit previously described to prepare the talking circuit and the circuit for operating back-bridge relay R105 as previously described, and also to short-circuit, at contacts'135, the winding of R190 to restore the latter. R150 restores in response to the restoration of R190. The call will then be completedr in a manner similar to that in'which the local call was completed.

Release of the switch train at the end of a call is similar tothat described for the local switch train.

If an inter-exchange call is to be made over a trunk requiring a repeater-e. g. when a connection to another type of system is to beestablished or when the completion of a reverting call requires the utilization of a reverting call switch in another exchange, it is necessary to remove the relays of the local control unit from the line. This is accomplished by wiring the selector bank contacts associated with the trunk line, over which said connections are to be made, as shown in Fig. 7A, wherein resistance 700 is of low resistance so that switching relay R120 will operate in series with said resistance. In a manner similar to that in which local connections were setup, connections may be completed to an idle trunk,

the contacts of which are wired as shown in Fig. 7A.

Assuming that the selector of Fig. 2 was used to make v such connections, the switching relay R220 will operate and lock itself in amanner previously described. R120 will operate in series with resistance 700 over a circuit extending from ground, over contacts 115, the lower winding of R120, conductor 199, conductor 235, contacts 227, wiper 244, the wiper contact connected to resistance 700,

- and resistance 700 to battery. At contacts 129, R120 completes a locking circuit for itself; at contacts 123 and 126, extends the calling line to relay R720, free of all control relays in the control unit of Fig. 1; and at contacts 128 opens the circuit for reoperating M200. R720 energizes over the calling loop and, at contacts 721, completes an obvious circuit for energizing relay R730. R730 operates to remove, at contacts 731, battery from the l private conductor 199 and to place ground thereon thereby to busy mark the trunk. When R120 operates, it also opens the operating circuit of line relay R100 at contacts V121 and 124 and extends ground over contacts 127b quence since they will restore after R restores in response to the restoration of R100. The call may now be routed to the distant exchange in a manner well known in the art.

Incoming toll calls Incoming toll calls will be routed by a telephone operator over a toll board trunk selector such as that shown in Fig. 8. Provision is made for preventing the automatic restoration of the ring cut-olf relay when a connector extends toll connections to an idle called line so that ringing of said called line can be controlled by the operator. Toll connections are set `up over the same group of intermediate selectors and connectors used for completing local connections, the necessity of separate toll train switches for operator-controlled ringing being eliminated. The control circuits of Fig. 8 are otherwise similar to those of Fig. l.

Assume that a toll call is routed by an operator to the toll board control unit of Fig. 8. Assume that said unit is connected to the selector of Fig. 2, the conductor 859 being connected to conductor 231, 869 to 232, 879 to 235, 889 to 233, and 899 to 234; that the selector of Fig. 3 is accessible to the selector of Fig. 2 and contacts 236, 237, 238 and 239 terminate in the selector of Fig. 3; and that the connector of Fig. 4 terminates in contacts 365, 366, 367 and 368. In response to impulses received by pulsing relay R800 over conductor 829, a toll connection will be set up over the first and the intermediate selectors under the control of the toll board control unit in a manner similar to that in which the local connections are set up, as previously described. Also the operation of the control unit and the connector in response to a third digit dialled by the operator will be similar to that described with respect to local calls. Therefore, at the end of the third digit, relays R800, R810, R830, R835, M400 and R840 will be operated; the connector wipers will be standing before the bank contacts of a group of lines associated therewith-which contacts we will assume include contacts 365, 366, 367 and 368; relay R830 will restore; relay R850 will operate in series with relay R840; R850, operating, opens the operating circuit of series relay R835 and control magnet M400, both restoring; M400, restoring, opens the operating circuit of R840 and R850, both relays restoring; and the ring cut-off relay is held operated over a locking circuit, all in a manner similar to that described with respect to the establishment of a local connection.

Now, when a fourth digit is dialled by the operator, relay R830 vis again operated in response to the restoration of line relay R800, and, at contacts 831, completes an obvious circuit for operating relay R860. In response to the fourth digit, the connector wipers are stepped by M410 to the contacts terminating the called line-e. g. contacts 465, 466, 467 and 468. If the called line is busy,

a busy signal will be put upon coil 898 by an operationV of busy relay R870 and a restoration of relays R830 and R860, in a manner similar to that described for local calls. The busy signal is induced into coil 897 and sent to the operator over conductor 809. If the line is idle, the switching relay R420 will be operated over a circuit similar Y to one, previously described, in response to the restoration of R860. As previously described, R420 will transfer the holding circuit of ring cut-off relay R440 to the extra to conductor 119 to busy mark the control unit. R100 releases. R and R170 operate but this is of no Consecontrol conductor 453 and relay R890 will operate in series with R440. However, when R890 operates, it completes, at contacts S91, an obvious circuit for operating switching relay R820. R820 operating before R440 releases, completes, at contacts 826, a circuit for holding R440 operated and for short-circuiting the winding of R890, said circuit extending from ground, over contacts 826 and 806, conductors 899 and 234, contacts 226, wiper 243, contact 238, conductor 3.45contacts 336, wiper 363, contact 367, conductor 453, contacts 429 and 445, through the winding of R440 to battery; and, at contacts 825, cornpletes an obvious locking circuit from ground at contacts selector.

pulses. selector radial stepping circuit will step both sets of wipers 4 812. R890 restores, R820-prepares the talking circuit at `"contacts 821 and 823,- and R440, remaining operated, keepsI the ringing current off of the called line. When the operator desires the called line to be rung,- she will cause relay R805 to be energized in a manner well known `in the art; and, `at contacts 806, the last mentioned holding circuit for R440 will be opened; R890 will again operate `in series with R440; R440 will restore when in series with the high resistance winding of R890; and at contacts 445 lby `the operator in a manner well known in the art.

Z700-line selector Referring more particularly to Fig. 9, it will be noted that both sets of wipers hunt simultaneously for an idle trunk, the upper set testing a trunk-in one group of trunks as the lower set tests a corresponding trunk in a second group. The selector is wired as `an intermediate selector similar to that of Fig. 3 as shown by the use of a release initiating relay R910 and battery over resistor 967; but obviously can be wired as a rst selector.

When said selector is seized by a previous switch after the initiation of a call, the control magnet M900 will operate in series with the series relaye. g. R145 of the local control unit. Except as otherwise noted, operation of this 20G-line selector is the same as that of a 1GO-line With M900 operated, stepping magnet M910 will step both sets of wipers to positions before predetermined groups of contacts in response to a series of irn- Control magnet M900 will be restored and the across bank contacts until an idle trunk is seized.

If two trunks, simultaneously seized by the two sets of wipers, are both idle, both switching relays, R930 and R940, will operate simultaneously. However, R930, op-

erating contacts 938 opens the operating circuit of `R940 and the latter restores. The call will therefore be extended `over the upper set of wipers.

. Obviously, if the trunk seized by the upper set of wipers is idle and that seized by the lower set is busy, the call will be extended over the upper set of wipers.

If the trunk seized by the lower set of wipers is idle and the other trunk busy, then only switching relay R940 will operate. At contacts 949, R940 will lock itself oper- ZOO-line connector with two sets of wipers Referring more particularly to Fig. l0, it will be noted that both sets of wipers simultaneously seize different outlets; that each set has access to G-lines; and that one control magnet, one stepping magnet, and one ring cut-oft relay are used for completing a call to any one of the G-lines. Also the operation of the 200-line connector is similar to that of the 10U-line connector unless otherwise noted, the connection to be made depending upon which of the two sets of incoming conductors is the set over which a call is being routed. Thus, if a call is routed' over the upper set of incoming conductors, a connectionwill be completed to an outlet'accessible tothe f upper set of wipers; and, if routed over'the lower set of conductors, `a connection will be completed to an outlet accessible to the lower set 'of wipers. The selection of the upper or lower set of incoming conductors would 'obviously be made in the next preceding stage in the switch train in a manner well known in the art.

Assume the connector of Fig. l() is seized over the upper set of conductors 1081, 1082, 1083v and 1084. The control magnet M1000 will operate together with the series relay of the control unit now controlling said connector. Pulses of the first digit received by stepping magnet M1010 over conductor 1081 and contacts 1042 will canse said magnet to step both sets of wipers to predetermined groups of outlets. Control magnet M1000 de energizes; and, in response to a second digit received, magnet M1010 will step each set of wipers to a predetermined outlet. `But obviously only the upper switching relay will operate if the outlets are idle, since only its incoming conductors are connected to the switch train over which the call is being routed. The call will be completed in a manner similar to that previously describe for a 10D-line connector.

A call routed over the lower set of incoming conductors will be extended over the lower Vset of wipers in a similar manner.

200-l1ze connector with one set of wipers Referring more particularly to Fig. 11, it will be noted that the bank contacts accessible to wipers 1181, 1182, 1133 and 1184 are arranged in l0 rows of 20 lines each; and that a lirst and second control magnets, M1110 and M1100 respectively, are used.

lt' the .connector is seized over the upper conductors 1161, 1162, 1163 and 1164, the proper connections `will be made under the control of M1110 to one of the irst l() lines of one row in a manner similar to that in which the lOO-line connector completed the connections.

However, asstuning a local call has been extended over the control unit of Fig. l and the selectors of Fig.- 2 and Fig. 3 in a manner previously described, to the connector of Fig. ll over the lower set of conductors v1165, 1166, 1167 and 1168, said connector will step its wipers under the control of the first `control magnet M1110 `to a predetermined row of outlets. in response to the first digit received, in a manner similar to that in which the connector of Fig. 4 operates. At the end of said first digit received by the connector, relay R will restore in a manner similar to that previously described; but now the second control magnet M1100 operates `in series with .R160 and R150 over a, circuit extending from `ground over contacts 1171, the lower winding of M1100, contacts 1113, conductor 1167, contact 367, wiper 3.63, contacts 336, conductor 345, contact 238, wiper `243, contacts 226, conductors 234 and 189, contacts 154, the winding of R160, contacts 149, through the winding of R to battery. R145 and M1110 restore, but M1100 is held operated over an obvious holding circuit includingvits upper winding and contacts 1105, andlR and and R150 are held operated-'over a circuit 'including con- 'tacts .1102, and similar to its. operating circuit.. M1100 operating and M1110 restoring complete at contacts 1104 and 1115 a circuit for operating interrupter relay R185, said circuit extending from ground, over contacts 1104, 1122, 1115 and 1133, conductor 1166, contact 366, wiper 362, contacts 334, conductor 34-4, contact `237, wiper 242, contacts 224, conductor 232 and 169, `contacts 125, 132, 175, and 162, and thence'through the winding restore, and R cannot re-operate ,since its operating circuit will be open at contacts 162;

nresponse to a second ydigit received,.the connector wipers will be stepped to a predetermined oneof thelast Y ten outlets of said predetermined line.

' ment.

At the end of the irst impulse of said second digit, the eleventh off-no1-- mal contacts 1169 will open; M1100 will restore; and, at contacts 1103, the operating circuit of switching relay R1130 will be prepared. Connections Lwill be completed in a manner similar to that previously described with respect to the connector of Fig. 4.

It will be noted that numerous combinations of the variou's selectors and connectors shown by applicant may be utilized in a switch train depending upon the requirements of' the exchange in question. The use of such combinations is well known inthe art and, it is felt, need not be discussed here.

The party line connector Referring more particularly to the party line connector shown in Fig. l2, it will be noted that the circuits differ vnoticeably from those of the connector shown in Fig. 4.

This is due to the provision for selective ringing- 5 codes being available for each line as shown. Ringing voltage is supplied over a typical minor switch arrangement in aV manner well known in the art. Except as otherwise noted, the operation of the party line connector is the same as that of the connector shown in Fig. 4.

Assume a call is extended by the control unit of Fig. l and the selectors of Fig. 2 and Fig. 3 to the connector of Fig. 12. Control magnet M1240 operates in series with relay R145 and, at contacts 1243, completes an obvious circuit for operating relay R1230. R1230 com pletes, at contacts 1234, an obvious circuit for operating relay R1220; and, at contacts 1233, prepares the circuit for operating stepping magnet M1250., Ring cut-off relay R1280 is operated by ground on private conductor 1214. .In response to a digit received, the connector wipers are stepped by M1250 to a predetermined group of outlets. M1240 restores at the end of the first digit received, thereby to prepare the switch for radial move- At contacts 1243, M1240 opens the operating circuitV of R1230; but the latter is held operated over a circuit extending from ground 'on the private conductor 1214, over radial Volf-normal contacts 1207, contacts 1237, through the winding of R1230 to battery. In response to a second digit received, the wipers are stepped to a predetermined outlet. Radial off-normal contacts 1207 open the holding circuit of R1230; but M1250, at contacts 1252, keeps R1230 operated until the end of the second digit when R1230 restores.

If the predetermined outlet is busy, ground on its private conductor is extended over wiper 1217, contacts '1236, 1242 and 1265, conductor 1212, and over a pre- Y viously described circuit to busy relay R180, the latter operating before R1230 restores. Busy signal is then relayed to the calling party in a manner previously de- Y scribed.

' tacts 1201, a circuit for operating the minor switch rez lease magnet M1200 is prepared; at the end of said third digit, R1220 restores to complete, at contacts 1222,

a circuitfor operating switching relay R1260, said circuit. similar to that for operating switching relay R420 of Fig. 4. yRinging current is supplied to the called line from a ringing generator (not shown), over conductor 1291, Vcontact 1292, wiper 1293, contacts 1294, the multipled contacts of the minor switch, the lower winding of R1280, contacts 1261 of switching relay R1260,

' 16 V contacts 1281v of ring cut-off relay R1280, wiper 1215, one side of the called line, the called substation ringing device, the other side of the called line, wiper 1216 and contacts 1283 and 1264 to ground. As with the operation of the connector of Fig. 4, R1280 will operate and lock when the called party answers.

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modiiications may be made therein, and it is contemplated to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention. Applicants preferred embodiment shows the selective switches stripped of the control means but it is obvious that each switch could have its own individual control means.

What is claimed is:

l. In a telephone system including an automatic switch having wipers with a normal position and having a single driving means together with a control magnet and an armature-controlled mechanism for causing an operation of said driving means while said'magnet is energized to move said wipers in one direction and for causing an operation of said drivingmeans while said magnet is deenergized to move said wipers in another direction, a calling line over which impulses are received, Vmeans associated with said line and switch responsive to the initiation of a call over said calling line for energizing said control magnet, means responsive to each impulse in a series of impulses thereafter received over said calling line forY operating said driving means, a changeover relay, means responsive to the termination of said series of impulses for operating said relay, means responsive to the operation of said relay for deenergizing said magnet, means for thereafter selectively operating said driving means and for switching through connections to said wipers, means responsive to the termination ofsaid call for energizing said magnet a second time, and an armature-controlled mechanism for restoring said wipers to normal in response to said second energization of said magnet.

2. In an automatic switch having a switching member with a normal position and having a single driving means together with a control magnet with means for causing an operation of said driving means while said magnet is energized to move saidV member in one direction and for causing an operation of said driving means'while said magnet is deenergized to move said member in another direction, incoming conductors over which said switch is seized and over which series of impulses are received, means responsive to the seizure of the switch for energizing said magnet, means responsive to each impulse in a series of impulses thereafter received over said conductors for operating said driving means, a changeover relay, means responsive to the termination of said series of irnpulses for operating said relay, means responsive to said operation of the relay for deenergizing said magnet, means for-thereafter selectively operating said Vdriving means and for switching through connections from said conductors to said member, means responsive to the initiation of the release of the switch for energizing said control magnet a second time, and a mechanism including the armature on said magnet operated and effective in response to said second energization of the, magnet for restoring said member to normal. Y

3. In a telephone system including an automatic switch with wipers having a normal position and including a plurality of lines, together with means for connecting a calling one of said lines to said switch, for sending impulses over said calling line and for thereafter disconnecting said calling line therefrom, said switch comprising a control magnet, means responsive to the connection of said calling line to the switch for energizing said magnet, a single driving means, means responsive to each impulse in a series of impulses received over said calling line for operating said driving means, armature-controlled ,means operated and effective in response to the energizet to `the termination of said `series of impulses for operating `said changeover relay, `contacts on said changeover relay operated for deenergization of the control magnet and for operating the interrupter relay, means responsive to the operation of said interrupter relay for selectively operating `said driving means and for switching through connections from said calling line to said wipers, armature- `controlled means operated and effective in response t'o the deenergization of the magnet for causing said last-mentioned operation of the driving means to move the wipers in another direction, means responsive to the disconnection oflthe calling line from the switch for energizing said magnet a second time, and an armature-controlled mechanism operated and effective only in response to said second energization of the control magnet for restoring said wipers to normal.

4. In a telephone system including an automatic switch with wipers having a normal position and including a plurality of lines together with means for connecting a calling one of said lines to said switch, for sending impulses over said calling line and for thereafter disconnecting said calling line therefrom, said switch comprising a control magnet, means responsive to the connection of the calling line to the switch for energizing said control magnet, a single `driving means, means responsive to each impulse in a series of impulses received over said calling `line for operating said driving means, armature-controlled means Operated and effective in response to the energizeton of said magnet for causing said operations of the driving means to move said wipers `in one direction, a changeover relay, means responsive to the termination `of said series of impulses for operating said relay, contacts on said relay operated to restore said magnet, con- -tacts on said magnet restored to restore said changeover magnet, said second mentioned means operated responsive to each impulse in a second series of impulses received over said calling line for operating said driving means,

`:armature-controlled means operated and effective in response to the deenergization of said magnet for causing, saidrlast-mentioned operations of the driving means to move said wipers in another direction, means respon- `isive only to the termination `of said `second series of impulsesfor switching through connections from said calling line to `said wipers, means responsive to the discon- ,nection of the callingline from the switch for energizing said `magnet a second time, and `armature-controlled means operated and effective only in response to the second energization of the magnet for restoring said wipers to normal.

5. In a switching system including an automatic switch having wipers with a normal position and having a `single `driving means together with a control magnet for causing an operation of said driving means while said magnet is energized to move said wipers in one direction `and for causing `an operation of said driving means while said` magnet isldeenergized to move said wipers in another direction, a control unit, means for extending connections from said control unit to said switch, means responsive to the completion of said connections for energizing said control magnet, incoming conductors associated with said control unit over` which impulses are received, `means in said control unitV responsive to each `of said series of impulses for operating said relay, means responsive to the operation of said relay for deenergizing said magnet, means for thereafter-selectively operating said driving` means byvway of saidtconnections and for extending said connections to said wipers, means for `or. said driving means while said magnet is energized to move the wipers in one direction and for causing an operation of said driving means while the magnet is deenergized to move the wipers in another direction, a control unit, a calling line over which impulses are received, means for extending said line to said unit, a primary one of said switches having connections to said unit, other switches in said plurality of switches accessible to said primary switch, means in said control unit operated when the line is connected to the control unit for energizing the control magnet in said primary switch by way of a first one of said connections, means in said control. unit operated responsive to each impulse in a series of impulses for operating said driving means in said primary switch by way of a second one of said connections, means in said control unit operated responsive to the termination of said series of impulses for deenergizing the primary switch magnet, means including said tirst connection operated responsive to said deenergization for selectively operating the primary switch driving means by way of said second connection, the Wipers of said primary switch thereby selecting one of said other switches, means operated responsive to said selection for extending said connections to said one other switch by way of said wipers and for energizing the control magnet therein by way `of said tirst connection, the fifth-mentioned means operated in response to a second series of impulses for operating the driving means in said one other switch by way of said second connection, the sixth-mentioned means operated in `response to the termination of said second series of impulses for deenergizing said last-mentioned magnet, means in said control unit for thereafter selectively operating said last-mentioned driving means by way of said second connection, the wipers of saidone `other switch thereby moved to a selected outlet accessible thereto, and means for extending said connections to said last-mentioned wipers.

7. `In a telephone system, a multi-directional selective switch, a control unit associated with said switch, a calling line, mea-ns for extending said line to said control unit, a control magnet in said switch, means for energizing said control magnet, means in said control unit whereby said energizing means is operated when said line is extended to said control unit, a stepping magnet in said switch, means for operating said stepping magnet, means in said control unit whereby said last means is operated responsive to each impulse of a series of impulses received over said calling line, a plurality of groups of multidirectional intermediate selective switches accessible to said first selective switch, means in said first selective switch for selecting one of said groups of intermediate switches, means whereby said selecting means is controlled by each operation of said stepping magnet while said control magnet is energized, means for deenergizing said control magnet, means in said control unit whereby said deenergizing means is operated inresponse to the termination of said series of impulses, means for selectively operating said stepping magnet, means whereby said last operating means is operated responsive to the deenergization of said control magnet, means in said iirst selective switch for selecting one of said intermediate switches in said one group, means whereby said second selecting means is controlled by selective operation of the stepping magnet while the control magnet isdeenergized, said first selective switch thereby selecting the rst' accessible idle intermediate switch in said Voney group, means forjenergizing the control magnet a second time, means in said control unit whereby said last operating means is controlled over said calling line, means for restoring said first selective switch to normal, and means whereby said last means is operated in response to a second energization of said control magnet after a first energization and deenergization thereof.

8. In a telephone system as claimed in claim 7, means Vin said first switch for switching through connections to nector switches accessible to said selected intermediate switch, means in said intermediate switch for selecting one of said groups of connector switches, means whereby said third selecting means is controlled by the operation of said second stepping magnet while said second control magnet is energized, means for deenergizing said second control magnet, means in said control unit whereby said last-mentioned deenergizing means is operated at the termination of said second series of impulses, means for selectively operating said second stepping magnet, means whereby said last operating means is operated responsive to the deenergization of aid second control magnet, means in said intermediate switch for selecting one of the connector switches in said one group, means whereby said fourth selecting means is controlled by each operation of the stepping magnet while the control magnet is deenergized, said intermediate switch thereby selecting the first accessible idle connector in said one group, means including a third of said connections for energizing the second control magnet a second time, said last means also controlled over said calling line by means of said release means, means for restoring said intermediate selective switch to normal, and means whereby said last means is controlled by a second energization of said second control magnet.

9. In a telephone system as claimed in claim 8, means in said intermediate switch for switching through connections to said selected idle connector, a third control magy net and a third stepping magnet in said connector, means including one of said last-mentioned connections for energizing said third control magnet, means whereby said last energizing means is operated responsive to the switching of said last-mentioned connections, means including a second one of said last-mentioned connections for operating said third stepping magnet, said last means and said fifth-mentioned means cooperating to operate said third stepping magnet in response to each impulse of a third and fourth series of impulses received, a plurality of groups of outlets accessible to said connector, means in said connector for selecting one of said groups of outlets, means whereby said last-mentioned selecting means is controlled by the operation of said third stepping magnet while said third control magnet is energized, means for deenergizing said third control magnet, means whereby said last-mentioned deenergizing means is operated at the termination of said third series of impulses, means in said connector for selecting a particular one of the outlets in said one group of outlets, means whereby said last-mentioned selecting means is controlled by the operation of said stepping magnet while said control magnet is deenergized, means including a third one of said last-mentioned connections for energizing said third control magnet a second time, said last means also controlled over said calling line by means of said release means, means for restoring said connector to normal, and means whereby said last means is controlled by a second energization of said third control magnet.

l0. In a telephone system having means for establishing local connections to a called line over a switchtrain including a primary local selector and a connector and having means for establishing toll connections to a called line over a switch train includinga primary toll selector and said connector, a ring cut-off relay in said connector, means responsive to the seizure of said connector for operating said relay, means responsive to the completion of a connection to a called line for restoring said relay, means operated and effective in response to said restoration of the ring cut-off relay for ringing said called line,

circuit means in a toll switch train for preventing the restoration of said relay, means in said toll selector controlled by a toll operator for opening said circuit means thereby to enable said fourth means to restore said relay to ring the calledline, said ringing means vthereby being controlled by an operator on toll calls.

l1. In a telephone system wherein local connections are established over switch'trains each including one of a plurality of primary local selectors and one of a plurality of connectors, wherein a toll board operator establishes toll connections over switch trains each including one of a plurality of primary toll selectors and one of said connectors used for completing local connections, a ring cut-off relay in each connector, means Y in the connector associated therewith for operating said relay, means whereby said operating means is operated when connections are completed to said connector, a locking circuit including one of said connections for holding said relay operated, means in said connector `for transferring said locking circuit from said one connection to a second oneof said connections, means in each primary selector for restoring said relay, means whereby said ringing means is operated in response to a restoration of said relay, means in each local switch train whereby said restoring means is operated responsive to said transfer of the locking circuit, means in each primary toll selector for short-circuiting said restoring means, thereby to prevent the restoration of said ring cut-off relay, means whereby said short-circuit means is operated responsive to said transfer of the locking circuit, means for opening said short-circuit Vmeans thereby to permit said restoring means to restore the ring cut-off relay, and means whereby saidlast means is controlled by the toll operator. Y

12. In a telephone system as claimed in claim 11,

' said means for restoring the ring cut-off relay comprising a high resistance relay and meanskfor operating said high resistance relay in series with the ringl cutoff relay over said locking circuit, thereby to cause said ring cut-oif relay to restore.

13. In a telephone system, a connector with one set of wipers for completing local and toll calls, said connector having aA single driving means together with a control magnet and magnet controlled means for causing each operation of said driving means while said magnet is energized to move said wipers in one direction and for causing each operation of said driving means while said magnet is deenergized to move said wipers in another direction; a releaseV circuit in the connector; means for extending connections to said connector; means operated when either a local or toll connection is completed to said connector for energizing said magnet; a ring cut-off relay in the connector;` means operated responsive to the energization of said magnet for operating said relay thereby to open said release'circuit; means controlled over saidconnection for operating said driving means, for thereafter deenergizing said magnet,

and for thereafter again operating said driving means;

`of incoming conductors associated with said switch, two

groups of positions available to said switching member, acontrol relay in said switchfassociated with only one of said sets of conductors, `means for operating said relay,"means whereby said operating means is operated `only in response to the termination of a first series of "impulses received `over said one set of conductors, means for moving said switching member, and means whereby Ysaid moving means is operated responsive to the operation of said control `relay to move said member a predetermined number of steps, whereby said switching member may be moved to a selected position in one group if `said relay is operated and to a selected posi- `ti`o`n in another group `if said relay is not operated.

15. In a switching system, a selective switch having vtwo sets of incoming conductors and a switching member with a plurality `of `positions arranged in two groups, a common `control unit with means for transmitting impulses, means for connecting said unit to said switch Yover either set of conductors, means for selectively mov- "ing said member in one direction, means `for selectively moving said member in the `other direction, means `whereby the first and second moving means are operated in response to a rst and second series of impulses received over one of said sets of conductors from said control unit, means whereby said first moving means is operated in response to a irst series of impulses re ceived over the other set of incoming conductors from said control unit, means whereby said second moving means is operated in response to the termination of said last-mentioned series of impulses, and means whereby said second moving means is again operated in response to a second series of impulses received over the other set of incoming conductors from said control unit, said switching member thereby being stepped to a selected position in one group if the connection is made over the one set of conductors and to a selected position in the other group if the connection is made over the other set of conductors.

16. In a switching system, a selective switch having a rst set of incoming conductors over which impulses are received when said switch is seized over said rst set of conductors and a second set of incoming conductors over which impulses are received when said switch is seized over said second set of conductors, means for seizing said switch, a switching member in said switch having a plurality of positions arranged in two groups, a single driving means in said switch for moving said member, means for determining the direction in which said member is moved by said driving means, means whereby said determining means is controlled over either set of incoming conductors, means whereby said driving means is operated responsive to a first and second series of impulses received over said first set of conductors thereby to selectively move said member in the one direction and then in the other direction, means whereby said driving means is operated in response to a rst series of impulses received over said second set of conductors thereby to selectively move said member in said one direction, means whereby said driving means is operated a predetermined number of times in response to the termination of said last-mentioned series of impulses thereby to move said member over a predetermined number of said positions in said other direction, means whereby said driving means is operated responsive to a second series of impulses received over said second set of conductors thereby to selectively move said member in said second direction, said member thereby being moved to a position in one group if the switch is seized over said first set of conductors and to a position in the other group if the `switch is seized over said second set of conductors.

17. In a combination as claimed in claim 16, means for restoring said switch to normal, and means whereby said restoring means is controlled by said determining means.

18. In a switching system, a selective switch having a first set of incoming conductors over which impulses are received when said switch is seized over said first set of conductors and a second set of incoming conductors over which impulses are received when said switch is seized over said second set of conductors, a switching member in said switch with a plurality of positions arranged in two groups, means in said switch `for selectively Amoving said member in one direction, means in said switch for selectively moving said member in another direction, a control magnet in said switch, an armature on said magnet having two positions, means whereby the position of said armature is controlled over said incoming conductors, means in said switch whereby said first moving means is rendered effective in response to said armature assuming one position, means in said switch whereby said second moving means is rendered effective in` response to said armature assuming the other position, means whereby both of `said moving means are operated responsive to impulses received over said incoming `conductors, and means whereby said second moving means is again operated a` predetermined number of times only if said switch is seized over said second set of incoming conductors, the control magnet and all of `said means cooperating in response to impulses received to move-:the `switching member to a` position in one group if therswitch is seized over the first set of conductorsand toa position in the other group if the switch is seized over the second set of conductors.

19. In a switch as claimed in claim 18, means for re storing said switch to normal, and means whereby said restoring means is operated when said armature assumes said one position for a second time.

20. In a telephone system, a switch with one set of wipers having access to two groups of outlets and with two sets of incoming conductors over which impulses are received, a control unit, means for connecting said unit to said switch over either set of said conductors, means in said control unit for transmitting impulses over said conductors, a control magnet in said switch, an armature on said magnet with two positions, means whereby said armature occupies one position when said unit is connected to said switch and occupies the other position upon the termination of a first series of impulses transmitted to said switch, means for selectively moving said wipers, means whereby said moving means is controlled for mov* ing the wipers in one direction when said armature occupies one position, means whereby said moving means is controlled for moving the wipers in another direction when said armature occupies the other position, means whereby said moving means is operated in response to a irst and second series of impulses received over either set of conductors, a control relay in said switch associated with only one set of said conductors, means including contacts on said magnet for operating said relay, means whereby said relay operating means is operated only in response to the termination of a first series of impulses received over said one set of conductors, and means whereby said moving means is operated a predetermined number of times in response to the operation of said control relay, said control magnet, control relay, and all of said means cooperating to move the wipers to a selected outlet in one group in response to impulses received over said one set of conductors and to a selected outlet in the other group in response to impulses received over the other set of conductors.

21.. In a combination as claimed in claim 20, means for restoring said switch to normal, means whereby said restoring means is operated responsive to the Varmature occupying said one position a second time, and means for causing said armature to occupy said one position a second time.

22. For use in a telephone system, a common control unit with incoming conductors over which impulses are received, a particular lirst selector associated therewith, said selector having access to a plurality of groups of trunks, certain of said trunks terminating in local switches and certain others of said trunks terminating in distant exchanges, means in said switch for selecting any one of saidtrunks, means in said control unit whereby said selecting means is operated in response to a series of impulses received over said conductors, means in said control unit for controlling a local switch terminating Vone of said certain trunks selected by said lirst selector, `means whereby said last controlling means is operated in response to a second series of impulses received, means 'in said control unit for transmitting impulses over a certain other trunk selected by said first selector to the distant exchange terminating said other trunk, means in said control unit whereby said last means is operated responsive to a second series of impulses and each series thereafter received over said incoming conductors, a repeater associated with a second one of said certain other trunks, a switching relay in said control unit, means for operating said relay, means whereby said relay operating means is operated only when said irst selector selects said second other trunk, contacts on said relay, means whereby said contacts are operated in response to the operation of said relay thereby to connect said incoming conductors to said second other trunk and to disconnect all of said control means and said transmitting f means therefrom.

23. A common control unit as claimed in c1aim.22 wherein said means for transmitting impulses to the distant exchange terminating said certain other trunk comprises a circuit including conductors of said certain other trunk, a relay individual to said trunk connected in said circuit, and contact means in said unit for short-circuiting said relay. v

24. In a telephone system wherein a common control unit in one exchange receives impulses over a calling line in said exchange and repeats said impulses to a common control unit in another exchange over a trunk line inter-connecting said control units thereby to eliminate the necessity for a repeater on inter-exchange calls, a series relay in said first-mentioned control unit, a line relay in Vsaid second-mentioned control unit, a circuit Y including said trunk line for operating Ysaid relays in series with each other, means for completing said circuit, means wherebyl said last means is controlled by a first series of impulses received over said calling line, means for short-circuiting said line relay, and means whereby said last means is operated in response to each additional impulse received over said calling line.

25. In the combination claimed in claim 24, a highresistance relay in said second-mentioned control unit, means for operating said high-resistance relay in series with said series relay and for removing said line relay from said circuit, means whereby said last means is operated upon the termination of impulses received over said calling line, said series relay restoring when in series with said highresistance relay, means for connecting said calling line to said trunk line, and means whereby said connecting means is operated in response to the restoration of saidseries relay.

No references cited. 

